feature high-pressure cleaning
Need to know facts about inlet supply for high-pressure pumps High-pressure cleaning is a versatile solution of employing relatively low-tech technology to produce a concentrated jet of hot or cold water to remove dirt and grime from surfaces, with or without chemicals. Keeping your highpressure system in optimum condition is especially crucial for those businesses operating high-pressure washers on a daily basis. With this in mind, Hawk Pumps, manufacturers of a range of quality high-pressure pumps, shares some technical tips on managing the crucial element of a high-pressure pump’s inlet supply.
The correct supply for the job An unsuitable inlet supply can cause even the best-designed high-pressure pump to malfunction and surprisingly serious problems can result from even the simplest of issues – or can go unnoticed by inexperienced machine operators. The most notable and common issue is pump cavitation. Remember: there is no standard setup for a high-pressure pump system, because no two systems are the same. However, by understanding cavitation and following a few simple rules, this issue can be prevented.
What is cavitation and how does it relate to inlet supply? Water is supplied to the pump through the inlet valves. It is important to note that the feed should be double that of the pumps requirement.
When a high-pressure pump is starved of water, the vacuum will result in water vaporising and this will cause cavitation. Also, any leaks in the inlet plumbing will allow air to be sucked into the pump. The best way to realise that your pump is cavitating is when it starts to vibrate and emit a very loud knocking noise. As the air or vapour bubbles are compressed, they implode and the resulting shock damages the pressure seals and valves. If the pump is run dry for a period, heat caused by friction on the plungers through lack of water, followed by bursts of cold water, could cause the ceramic pistons to shatter. The back end of the pump can then be destroyed as a result of the cavitation. As a result, damage is then caused to the conrods, the plungers
Cavitation completely destroys back-end of pump.
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African Cleaning Review March/April 2021
and the crankshaft. Cavitation also causes seals to wear and the valve plugs to burst. When the crankshaft seizes it causes the motor or engine to seize, destroying more than just the pump. The best way to avoid this is to ensure that the water supply is sufficient for the pump and that no air is able to enter the water feed.
How to ensure the inlet supply is sufficient Pumps with a flow rate of less than 15 L/min A connection to a domestic tap may be used for pumps that have an output of less than 15 L/min, as long as the water supply is not shared. The water pressure must also be fairly consistent. The water supply can be provided through one inlet.
Cavitation causes ceramic pistons to shatter.
